"You guys do a great job," he wrote. "When I was 7, I washed dishes and my mom cooked in a diner just like this. We were dirt poor and didn't have money for Christmas. Hopefully, this will help all of you have a better Christmas."

The man behind the generous tip, Aegis Living CEO Dwayne Clark, has been a customer at the Brief Encounter Café for the past eight years. (Owner Melanie Bard told ABC News that Clark and his wife regularly eat there on the weekends.)

Clark said he wanted to do something kind "in appreciation of my mother, who's not with us anymore, and because of the Christmas season." He adds that as a kid, he "saw how hard my mom worked for people who weren't always appreciative."

He says he hopes that his gesture will start a trend of showing the people around us that their hard work doesn't go unnoticed.

"You don't have to give money. You can write appreciative notes and say thank you," he told ABC News. "It would go a long way to nourish all of us."